Mutual information maximizing linear precoding for parallel layer MIMO detection

In this paper mutual information maximizing linear precoding for MIMO transmission using finite signal alphabets and a parallel layer MIMO detection scheme is derived. The derivation exploits that the mutual information of the parallel detection scheme can be expressed in terms of the mutual information associated with optimal maximum likelihood detection. Results show that the large performance gap between parallel layer detection and maximum likelihood detection in ill conditioned channels can be substantially alleviated by optimal precoding.